Ok Richard, I had a look at the Haynes wiring diagram and I reacon that you should see 12V when you crank the engine only or the engine is running. If not this is the reason why you cannot start your car. If you hot wire the pump and the engine still does not start then the problem is not likely to be the fuel pump relay.

According to my reading of the diagram (page 12.27 Haynes Manual) here is what is happening.

The Ignition switch will provide power to the ECU when ignition is turned on. ECU will then power up the main relay (165). The main relay if it is working will drive fuse 16B to 12V. So if you do not see 12V at 16B with ignition ON suspect main relay first. If you get 12V then the main relay is good.

The main relay through fuse 16B powers the injectors, and a number of engine management sensors but also powers the fuel pump through the fuel pump relay (166). The fuel pump relay is activated by the ECU and it should then provide 12V to Fuse 32 when the engine is started or cranked up.

The ignition switch power delivery is only to the ignition coil through Fuse 17 which seems to be OK in your case.

My main suspect based on this investigation is got to be the Main Relay (165) simply because it has to supply power to a lot of circuitry including the fuel pump.

Second suspect ECU. By some reason the ECU does not think there is a need to activate the fuel pump or activate the injectors. Malfunctioning CPS can be one reason, but other like ignition switch or even alarm/immobiliser can be a reson. You can check to see if the ECU is activating the the fuel pump relay by measuring the voltage at pin 14 in the diagnostic socket (181). The voltage there with ignition ON should read 12V but when engine is started or crancked the ECU should ground the voltage so that fuel pump relay is activated. If this is not happening then you know the ECU is not controlling things while the fuel pump relay is probably OK.

Third suspect - Fuel pump relay. If ECU activates the relay but no 12V at the fuel pump Fuse 32, then relay is at fault.

Hopes this will draw some light in your investigations.

Makis

posted by 82.44.178...

• Swedecar - No voltage at fuse#32 - Measured correctly, Richard, Thu, 20 Jan 2005 14:48:40
  • Re: Swedecar - No voltage at fuse#32 - Measured correctly, Makis, Thu, 20 Jan 2005 16:10:08 <-- Viewing This Message
    • Voltage fluctuation at fuse #16b, Richard, Thu, 20 Jan 2005 16:42:54
      • Re: Voltage fluctuation at fuse #16b, SWEDECAR , Thu, 20 Jan 2005 18:17:15
        • Thanks, - I wish I was in LA, Richard, Thu, 20 Jan 2005 20:02:04
      • Re: Voltage fluctuation at fuse #16b, Makis, Thu, 20 Jan 2005 17:05:50
        • If Main Relay Bad ... ?, iveand , Thu, 20 Jan 2005 17:26:01
          • Re: If Main Relay Bad ... ?, Richard, Thu, 20 Jan 2005 18:01:04
    • Thanks for the great info., Richard, Thu, 20 Jan 2005 16:27:08

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